1. Field
Embodiments of the present invention relate to an LED flash lens which is mounted on a photographing apparatus, such as a camera, used as a subsidiary light source of the photographing apparatus during photographing, and allows LED light to be concentrated on a photographing region so as to enable high quality of photographing to be carried out.
2. Description of the Related Art
In general, xenon lamps and LEDs have been mainly used as light sources of flashes. A xenon stroboscope of a xenon lamp may emit sufficiently bright light but has a large volume of other parts except for a light emitting part, thus being mainly used in a large-size digital camera. On the other hand, an LED stroboscope of an LED flash may be miniaturized but does not have sufficient brightness. Therefore, the LED flash requires high light concentration, and thus if light concentration is required, a condensing lens may be installed to improve light concentration.
Further, in order to intactly display the inherent colors of an object with a flash using LEDs assisting a photographing apparatus, the flash needs to emit white light the most similar to natural light.
In order to form white light using LEDs, there is a method of forming white light by mixing three primary colors of light, i.e., red, green and blue. However, this method is not easy to be substantially implemented, particularly in the case of the LED flash requiring light concentration. Therefore, a method of forming white light by using blue chips as LEDs and applying a phosphor to the blue chips has been most universally used.
However, in the case of such a technique of forming white light by applying the phosphor to the blue chips, yellow bands or yellow rings having concentric shapes occur. When the yellow bands or the yellow rings occur, white light decreases in value.
It is recognized that occurrence of the yellow bands or the yellow rings in the LED flash field in which the phosphor is applied to the blue LED is the most important problem to be solved.